Spiral film spray nozzle



Oct. 2, 1951 J. u. BETE SPIRAL FILM SPRAY NOZZLE Original Filed Feb. 26,1946 Reissued Oct. 2, 195 1 SPIRAL FILM SPRAY NOZZLE John U. Bete,Greenfield, Mass., assignor, by mcsne assignments, to Bete Fog Nozzle,Inc., Greenfield, Mass., a corporation of Massachusetts Original No.2,518,116, dated August 8, 1950, Se

rial No. 650,341, February 26, 1946. Application for reissue May 25,1951, Serial No. 228,332

Claims.

Matter enclosed in heavy brackets appears in the original patent butforms no part of this reissue specification; matter printed in italicsindicates the additions made by reissue.

This invention relates to a spray nozzle and its principal object is toprovide a nozzle which is of simple but durable construction, efiicientand reliable in operation and embodying a design which may readily bevaried so as to obtain the desired spray characteristics.

Further objects relate to various features of construction and will beapparent from the consideration of the following description and theaccompanying drawings, wherein:

Fig. 1 is an elevation of a spray nozzle constructed in accordance withthe present invention;

Fig. 2 is a vertical section through the nozzle shown in Fig. 1;

Fig.3 is an elevation of the insert; and

Fig. 4 is a cross section through a thread or vane of modified form.

In accordance with the present invention my spray nozzle comprises agenerally tubular member having a body portion defined by one or morehelical threads or vanes, one end of the tubular member defining aninlet and preferably being formed so as to provide a connection with apipe line or the like. The opposite end of the tubular member isprovided with a generally conical insert having its tapered portionextending inwardly in coaxial relation and preferably coextensive withthe helical vane or vanes. With this construction and arrangement,variations in the type and character of the spray may be had by varying(a) the lead or pitch of the helical vane or vanes; (b) the number ofvanes, i. e., single, double, etc.; (0) the length and shape of theinsert; (d) the angle and shape of the active surface of the helicalvane or vanes; and (e) the diameter of the helix defined by the vanes.

With a given tubular member having uniform helical vanes, the spraycharacteristics may be modified by varying the shape of the taper-edinsert, an insert having a, surface contour presenting a generallyparabolic shape producing the maximum degree of fineness of spray,although a straight taper, i. e., ageometric cone, produces satisfactoryresults and has the further advantage of being more economical tomanufacture. Special spray patterns, e. g., coarse outside cone and fineinside cone, may be obtained by using inserts having different shapedsurface contours. The size and shape of the entrance inlet or throat mayalso be varied to obtain different effects, but for general use, a highvelocity jet is usually desired, and to this end a Venturi throat isrecommended.

A full cone spray may be obtained by varying followed with a 90 cut overa portion of its length, or a combination of two or all of thesemodifications. Thus, an unlimited number of spray patterns andcharacteristics may be obtained from the same basic arrangement ofparts.

Referring to Figs. 1 to 3, which illustrates what is now considered apreferred embodiment particularly suitable for use as a sprinkler in afire protection system, a length of metal rod of hexagonal crosssection, turned down to form a cylindrical body portion I and ahexagonal coupling head 2 is bored or drilled axially to provide acentral channel 4 communicating with a Venturi throat or inlet 5 formedin the head 2. The outer end of the head 2 is turned down and threaded,as shown at 6, to provide a coupling element for attachment to a pipe orother conduit, and the body portion is milled or cut away to form a pairof helical threads or vanes 8 and 9 of generally trapezoidal crosssection.

A generally conical insert N) (Fig. 3) having a surface contour ofapproximately parabolic curvature, is disposed within the channel 4 withits enlarged end sealing the outer end of the channel, and its taperedbody portion extending coaxially into the channel with its inner endterminating at or adjacent to the inner end of the throat 5, as shown inFig. 2. A set screw 12, carried by the lower end of the tubular body I,holds the insert l0 securely in place.

The sprinkler head herein shown may be screwed into a socket equippedwith a fusible plug or the like, and when put in use, the high velocityjet issuing from the throat 5 is progressively diverted outwardly by theinsert H) as it travels the length of the vanes 8 and 9, so that itimpinges upon the inner edges of the upper faces 14 and I5 of the vanesand is directed outward along said faces and is thus transformed into arelatively fine conical shaped spray.

If it be desired to increase the fineness of the spray, the upper oractive surface of each vane I!" may be stepped, as shown in Fig. 4, toprovide a relatively narrow inner surface l6 spaced above the outersurface ll. This particular design appreciably reduces the frictionalresistance of the fluid passing over the active surface of the vaneswithout materially reducing the mechanical strength of the spray nozzle.

While I have shown and described one desirable embodiment of theinvention, it is to be undertrally in said jet and having a surface ofrevolu stood thaitthis enclosure is to! theipurpOSeibflilitionienlarging in the dineetion of Eflow or the jet lustration and" thatvarious changes andmodifialong"smoothlycontinuous-lines=curving from aCations y be made Without departing from the :sdirection partly radialat the apex toward a more spirit and scope of the invention as set forthin nearly axial direction to divert the jet flow prothe appended claims.gr'essively- -ontward in annular formation around I claim:ssesaidicoreimem-ber and a vane winding helically l. A nozzle f p ineacontinuouspir atoundesaid core-member and said annular jet Comprising agenerallyifiyiindliba'l membersandihdvingiansactive surface inclinedupward at the inte d ate portion Which is Cut y an angle to said'aaz-isand also winding around said form a Co t uo s helical threadlhaving r ai-core,memberwin.helical formation and ,having a t y parallel inner and6111513135Wainsfiwithiidd- ,ffre'e inn'er'jedge atysubstantiallyconstant distance joining faces that are a y e i he -,fromft he,sa1blamis so as to be spaced progressively inner l Of Said thread being ofgreater Width nearer tot/1e surface of said core member, the y'et thanthe outer Wall and defining a M -IS issuing" from said throat beingprogressively of substantially uniform. diameter, one end oftsaid e aioiward.insaidannu ar, f rmat n Said cylindrical'member providing a flllidlinlt fiilda m along thetzen g th o a -w generally coniealinsert inthe 'otheibndwf 'pingg on" the said inner "edge" of the active guyy dril me wi h i tapered d portion face thereof to be transformed into arelatively extending towardsaidinlet and coaxially within fine smwgSaid'helical threadv Anoezlefor producing a spray directed out- 2. Anozzle forpro'd'ueing' a continuous-spiral gwa d r nd an axiscomprisinga generally m. filmQcomDriSing a genifiillycylind'lica1member, bularmember having a throat portion receiving"theintermediate'portionoffwl ich is'cut awa'yto I 'i m supplyv andfarming it into a jet amdnd i vfofm continuous helical thread fapproximate '25 saidaxis, a core member coaxial'with saidtubu- T.trapezoidal-Shaped'" =ioss:seciion, inner lar member and, positionedcentrally in s aid ret "Wall O saido'thread'being o r e Width than andenlarginginthe direction of flow of the jetithe'outerw'alland'defininganaxial bOreofsub- 15 ve t thjet";flow'.p7f0gr888i2)l3j outward in s'tantia11y"'uniform diameter;oneend of said cyannular formation around said core member, and

fir r g 'fl inlet'havingw amvaneflwinding. helically, around saidcoreflmern- I a n i 'Wa11' frme with venturifthmat' benand, saidannularjet andhaving a telfltizzely a a q n j is i i the" other. narrowactive surface less than the maximum T9 i cylindrical r ih a a. axialthickness of; thevane andinclinedoutward portion extendingi'towardsaidinlet and coaxially at an angle to said axis and dlsowmdmg around Wtthmk e r V a said corememben. in helicalformationandhavfor P fqmt i m inganinnerv-edge spacediprogressively nearer to y n t 53 F3 i member "thesurface of said core member s othat as. thejet 1t i te port on of w ic ato issuing from saidthroatisvrogressi-velgdinected .h' F m "having sOntwatd inannular formation byvsaid. core memfstannavloly parallelmnerand'outer Wang wlth'ad' her it. travels the lengthof said vane andimpinges 'fijoining faces that are outwardly convergent the .lonltheinneredge of..the active face thereof to be "innerwall of saidthrea'dbeing" of g'reaterwidth etrransfm'gmedlmto relatively fine spray "thanthe'outenwalkand defining an axial bore of "substantially"uniforindiameter,'t.one"endoi ."JOHN' U- B T said cylindrical member'providi'ngafluidinlet, 1r,

the adjoining "face of said'thread opposing the E CITED fiilid fl j g' SDD p "Theifollowing' ereferen'ces 'are of record in the vide-arelatively-narrow Surface spaced inwardly filebfthis-patent or 'theoriginal patent:

of'and axially offset from the-outer surfacepor- I non thereof; a'ndagenerally'conical insertin the UNITED STATES; PATENTS other end' ofsaidcylindrical rnember withits Nii'm-ber 'Name Date tape'red-end-portion'eXtending-towardsaid inlet I -'-'Hansen Aug. 11; 1925 "and coaxiallywithin said-helicarthread. 2 'scofield *Dec.- 10,;- 1940 4; A nozzle f rproducing a spray directed up- 2,'359,171 'Tarbox Sep-t.'26;.'1944 wardaround an amis-comprising 'a generallntu-a bular member having athroat-=portion receiving "FOREIGN'PATENTS 'a-liquid su pl and formingit into-a jetaroand Number 1 il'icountry -D said axis, a generallyconicdl core 'm-mber cbam- 501L109 Jan-1 ial with saidtubular'rnemberand positioned-cen-

